Hey guys been a while and I thought I was getting to know theses trucks good. However I am a bit stumped here with a Wierd issue I have been chasing for a while now.
the engine will almost stall when either driving and coming to a stop with the clutched engaged and in gear or just reving it.
I jumped the clutch switch to bypass that without any change. While in neutral it doesn’t do it at all and only in gear. My clutch does appear to be dragging as u can feel it while putting in gear. Could this be the issue? A slightly dragging clutch causing the stumble while in gear?

thanks for any input and suggestions

 

Just wanted to update the post as I hate when they go unresolved. Changed plugs to oem Ngk and gapped at .044 with no difference I then re checked timing and set idle to spec with my timing light tach with no change….I then decided to go out on a limb and set the idle higher and check to see if the stumble was still there bu about 50 rpm stages. Well turns out at about 980 rpm no more stumble and drive ability is much better. So if anybody else comes across this issue of a stumble when rpm drop but only in gear. This was my fix for the issue. I am still going to check for any vac leaks once the weather gets warm but for now it’s fixed in my mind

 

I would still replace your Clutch Switch.......it can have a broken spring inside of it, not allowing it to operate as it should. Here is a link to one on Ebay......

https://www.ebay.com/itm/374072618545

Edit: Since the Ebay link no longer works (duh!) I am posting the pics of a new Clutch Switch (NOT the Starter Inhibit Switch!)

 

I kinda ruled it out a few different ways, first with a multimeter and checking to make sure it stayed closed through out the range. Multiple times slow and fast. Then jumped the feeds on truck side and ran it that way with same stumble. Unless this switch is a variable resistor and ecm is that good, figured it couldn’t be switch.

To be honest I am also wondering if my temp sensor is causing or a vap lock cuz my temp gauge doesn’t work with single pole sensor I already changed cuz if gauge is working when grounding the wire. So replaced sensor. And gauge still isn’t working.

checked plugs multiple times through out and not running rich. Actually was running lean and hence resulting in new tank, I rebuilt sending unit and new pump, new filter and finally have good fuel pressure through out its running. Last change they looked good even coming out but went to Ngk cuz I am wierd like that.

also kinda ruled out a few things by putting transfer case in neutral, with switch connected ran same test and it still did it’s stumble. And once again only in gear which was even more Wierd.
I assume whatever the ecm demands when in gear to compensate for load. Affected it too. But clutch and switch nothing.

time will tell and if it turns out that I gotta pull it off and out I will def take some pic and let u guys know for sure. I got some really good pics of the trouble this truck caused me so far

and I appreciate any input very much!

here is the old girl as she sits